Question

What is the pH of 5.0 L of an aqueous solution that contains 1.0 grams of HBr and 1.0 grams of nitric acid

Answer 1

Hello!:

Molar mass:

HBr = 80.91 g/mol

HNO3 = 63.01 g/mol

Number of moles:

moles HBr =  1.0 / 80.91 => 0.01235 moles of HBr

moles HNO3 = 1.0 / 63.01 => 0.01587 moles of HNO3

So , total moles of H⁺ :

0.01235 + 0.01587 => 0.02822 moles of H⁺

Molarity of solution:

M = n / V

M = 0.02822 / 5.0

M = 0.005644

Therefore:

pH = - log [ H⁺ ]

pH = - log [ 0.005644 ]

pH = 2.25

Hope that helps!